J. D. E. Holmes 
305 
No reports have been received by me on the results of the treatment 
of Surra in the districts. Captain Dawson in the Indian Veterinary 
Journal, Yol. I. No. 3, states that Mr Gibson, Director of the Vaccine 
Institute, Madras, has tried the treatment with complete success. 
Conclusions. 
I. The results herein recorded are further evidence that arsenic is 
a specific for Surra in horses ; that a permanent cure is effected, and 
not merely a temporary tolerance of the disease; that the treatment is 
simple, and that by careful dosage 70°/o and upwards of Surra cases, 
even when contracted spontaneously and in the last stage, can be cured. 
II. Arsenic is best administered in form of arsenious acid, in 
bolus or in solution. Atoxyl is a convenient form of giving arsenic 
hypodermically. 
The methods of dosage which have been found successful are : 
(1) Arsenious acid alone. This is given in bolus, in gradually 
increased doses, with one day’s interval between each dose. Eight 
to ten doses are sufficient. 
(2) Atoxyl and arsenious acid, given alternately in gradually 
increased doses, with one day’s interval between each dose. Five 
doses of atoxyl and five doses of arsenious acid are sufficient. 
(3) Arsenious acid in solution, atoxyl and arsenious acid in bolus. 
The dose of arsenious acid solution is followed by atoxyl, and arsenious 
acid, in bolus, on successive days. The doses are repeated once or twice 
after an interval of four days between each series, and finally after an 
interval of eight days. 
III. The success of the arsenic treatment of Surra depends chiefly 
on the strict observance of the following principles: 
(a) Arsenic must be given in full sub-toxic doses. Care should be 
taken, especially in the earlier part of the treatment, not to administer 
doses sufficiently large to cause symptoms of poisoning, such as colic, 
loss of appetite etc. If this occurs, treatment should be suspended 
till the animal has completely recovered. In the meantime, occasional 
injections of atoxyl should be given as required. 
(b) Arsenic must be administered at intervals, and not continuously 
day by day. In the systems of dosage (1) arsenious acid alone, and 
(2) atoxyl and arsenious acid alternately, experience has proved that 
one or two days’ interval between doses is necessary. In many ex¬ 
periments where the doses were given daily, and also when the 
